Planograph co



C. E. DAVIS.

SURGICAL SNARE.

APPLICATION FILED FEB. 14, ms.

Patented July 22, 1919.

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UnrrEn STATES PATENT oFEroE.

CHARLES E. DAVIS, or NEW YORK, n. Y., nssrcrnon T0 FRANK E. MILLER, on NEW YORK, N. Y.

SURGICAL SNARE.

Specification of Letters Patent.

Application filed February 14, 1918. Serial No. 217,076.

To all whom it may concern Be it knownthat I, CHARLES E. DAvIs, a citizen of the United States, and a resident of the city, county, and State of New York, have invented certain new and useful Improvements in Surgical Snares, set forth in the following specification.

This invention relates to surgical instruments employed in the removal of tonsils and like operations. The object of the invention is to improve the manner in which a snare may be contracted and released both at will and automatically. The above and further objects of my invention will better be understood by reference to the following specification and claims, which are directed to the illustrative embodiment shown in the accompanying drawings in which like char acters designate corresponding parts in the several figures, and in which- Figure 1 is a side elevation, with parts broken away complete instrument;

Fig. 2 is a top plan view, with parts broken away, of the structure shown in Fig. 1; y

. Fig. 3 is a fractional side elevation of the instrument viewed from the opposite side to that shown in Fig. l;

Fig. 4 is an end view of the operating tip, with the snare wire shown in section;

Fig. 5 is a longitudinal section through.

the operating tip; and

Fig. 6 is a top view of the nipple at the end of the operating tip showing the anchorage for the snare wire.

Referring to the drawings, a long steel draw needle 1 guided in the tubular stem 2 is provided, with the usual wire gripping eyes in its forward end 3 and at the rear, on one side only, is provided with ratchet teeth 4. The stem 2 is fixed to a breechframe 5. In the cavity6 of the breechframe 5 a spring detent 7 is located and operates to press and catch into the teeth 4. The breech-frame 5 extends downwardly and rearwardly into the hand-grip or handle 8. The operating leverv 9 is hinged by the pin 10 to the lips 11 extending out from the breech-frame 5. A link lever 12 is hinged to the breech-frame 5 by the pin 13 and at its lower end has a slot 14 in which the pin 15, itself fixed to the upwardly extending lips 16 of the lever 9, operates to force rearwardly a pawl 17 hinged by the pm 18 t0 and parts in section, of the one endof the link lever 12 and itself spring pressed against the ratchet teeth 14 by a spring 19. c

A rearward movement of the arm 9 causes the pawl 17 to force the needle 1 rearwardly, in which position it is held by the detent 7 while the spring 20 returns the arm 9 to original position ready for another rearward step of the needle 1. A finger hold 21 is fixed to the rear end of the needle 1 and is serviceable to causea rearward movement of the needle 1 against light resistance,that is, until considerable force is required to cause a rearward movement of the needle. It is also obvious that, if the needle 1 should be rotated upon its axis until the ratchet teeth 4 disengage the pawl 17 and the detent 7, the needle 1 may be moved freely either forward or backward so far as the manipulating mechanism is concerned. Some surgical snares have been made in which there was nothing to prevent an accidental rotation of the needle and its consequent accidental release when no release should have been permitted. To overcome this my apparatus is provided with a combined guide-lock and quick manipulator25, which is fixed to the rear end of the needle 1 and comprises a guide bar 26 adapted to slide along the side of the breech-frame 5.. The forward end of this bar 26 may be provided with a finger hold 27 useful for manipulation by a forefinger to cause a quick adjustment of the needle 1. The engagement of the bar 26 against the side of the breech frame 5 prevents rotation of the needle 1 in one direction while rotation in the other direction may be prevented by the pivoted clip 28, the pin 29 of which is rotatably mounted in the handle 8. The automatic release of the pivoted clip 28 is effected by a cam 30 carried on the outer face of the bar 26. Although when the cam 30 engaged the upper end 31 of the clip 28 to turn it counter-clockwise, as viewed in Fig. 3, this merely permits the bar 26 to swing out but does not force it to swing out to cause a rotation of the needle 1 and the consequent release of the ratchet teeth 4. To insure an automatic release when a complete rearward movement of the needle 1 has been effected, I provide a cam 34 which may be fixed b0 the lip 11 and which has an outward extension 35 functioning LO engage the inner edge of the finger hold 27 when 16 is cut through the threads 44 so that a bight may be formed in the snare wire 45, which serves as a positive anchor when the nipple ll-is screwed home into the socket 40. By thisarranqement only the leg 50 of the snaie' 511'islliavvn in when the needle 1 is retracted. "This has niuchadvalitage for certain operations.

The dotand dash lines in Fig. 1 indicate the position of the bar 26 when a 180 rotationof the needle 1 has been efiected.

" What Iclaimand what I desire to secure by United States Letters Patent is "T1. In a surgical share a retracting needle provided with ifatchet teeth on' one side; pawl and detent mechanism for 006 )erating with sifid ratchet teeth; a guide bar forpra venting the o'tation of said'needle; and a releasable 'eatch'for' cooperation with said 2} In a surgical snare a retracting needle provided: with mailer teeth on one side;

awl' and detent mechanism for cooperating with ,sai'c" ratchet teeth; guide bar for 'preventing he rotation of said needle; a releasable catch for cooperation with said "ide barfa'nd means on sai'd'guide barfor alltbfl 'latlcall'y releasing said catch.

3. In a surgical snare a retracting needle provided with ratchet teeth on one side; pawl and detent mechanism for cooperating with said ratchet teeth; a guide bar for preventing therotation of said needle; a releasable'eatch for cooperation with said guide bar; means on said guide bar for automatically releasing said catch; and means for automatically rotating said ratchet teeth out of engagement with said pawl and detent mechanism to release said needle.

4. In a surgical snare a retractorcomprising a rotatable bar having ratchet teeth of limited circumferential extent along one side pawl and detent mechanism for retra'cting said retractor by engaging said ratchet 'teeth but inoperative hen said bar is rotated to disengage sai'dteetli'; independent meansfor effecting a quick retraction of said bar; and releasable means for locking said bar'against disengaging rotation but permitting longitudinal jinovemen't 61 said bar.'

5, In a surgicalsnare a retractor comprising ar'otatable bar haying ratchet'teeth of limited circumferential extent along one side; pawl aiid detent mechanism r m; 'retra'cting said 'retractor by engagingsaid ratchet teeth but inoperatiye when said bar is rotate'd to disengage said teeth g relelas able means for lookingsaicl bar agai stdisdinal increment of said bar jand'mea ns for automatically releasmg sai lf'me'ans for lock- Washington, 135' G3 1 eats t r. 

